Connector systems for interfacing diagnostic or analytical devices with an outside source of data are known. Generally, a connector system comprises at least two electrical interfaces, one on each of two sides of a connector module. On the first side of the connector module, the connector is interfaced with an outside source which generates a signal that is indicative of the state of a system under observation or otherwise activated. On the second side of the connector module, a second interface is provided to bus the signals from the outside source to an analytical or diagnostic device for analysis and data processing at an input/output port. Examples of such devices are ultrasound equipment, radar equipment, computer equipment, and other electronic devices which have an input interface. Connectors have been designed for use with all such devices and others.
In more sophisticated systems which implement high speed data links from the outside source to the device, the connector interfaces can become very complex. To achieve high integrity data communications between the outside source of data and the device, prior connectors have been designed to accommodate high density contacts so that increased data flow through the connector at high frequencies and at high speeds can be achieved. Examples of such connectors and connector systems are found in U.S. Pat. No. 4,699,593, Grabbe et al., and U.S. Pat. No. 4,927,369, Grabbe et al., the teachings of both being specifically incorporated herein by reference.
In the connectors such as those disclosed in the Grabbe et al. patents, the individual electrical interface contact members in the connector modules are usually on 100 mil centerlines which causes the size of the connector modules to increase dramatically as the contact count increases. Furthermore, the actuation forces necessary to achieve the interface between the second side of the connector and the device are greatly increased as the number of pins increases, thereby increasing the possibilities of misalignment of the connector and failure of the data interface. Additionally, many of these prior connectors are utilized in a manner requiring only a relatively small number of mating/unmating cycles.
Connectors to accommodate high contact densities for use in high speed data devices may comprise a plurality of modular connectors with electrical interface contacts as described above and a printed wiring board to which the modular connectors are plugged. The printed wiring boards contain a plurality of circuits that are adapted to communicate the data from the outside source to the device which processes the data. The contact surfaces or pads on the printed wiring boards are typically interfaced with a substrate in the device which is further adapted to receive the communicated data from the outside source. This substrate may be yet another printed wiring board, printed circuit board, or other electrical receiving device which can interface with the contact pads on the printed wiring board in the connector.
When high density contacts are required, an interposer is also oftentimes provided to establish a connection medium between the printed wiring board in the connector and the substrate An "interposer" is typically a land grid array which effectuates and/or facilitates contact between the printed wiring board and the substrate in the device. Such interposers are especially useful when the closely spaced contact surfaces on the connector modules prevent a direct interface from the electrical interface contacts in the connector modules on printed wiring board to the device. The interposer thus provides a separate set of contact elements which must be firmly secured against both the printed wiring board in the connector and a printed wiring board in the device.
It has been found that interfacing the contact pads of a printed wiring board in a connector to another substrate to achieve sufficient electrical contact requires sufficient force to hold the contact pads firmly against the substrate during operation of the device. Typically, the printed wiring boards have merely been screwed or otherwise mated in connectors and brought into contact with the interposer or other substrate which is permanently mated to the device. Through the pressure applied during mating of the printed wiring board to the substrate, the contact pad is pressed to the substrate. However, applicants have recognized that this is frequently an unsatisfactory method of ensuring adequate electrical contact.
Accordingly, applicants have come to appreciate that it would be desirable to provide a connector or connector system having a printed wiring board with the ability to firmly mate the printed wiring board thereof to a-substrate in a device so that data can be bussed to the device through the connector with high reliability. Furthermore, it would be desirable to provide a connector which is both matable and dematable so that the connector can be used with various devices and/or frequently reused with the same device. Such a connector would be both versatile and rugged. Additionally, sufficient means should be provided to the connector to ensure adequate electrical contact of a printed wiring board therein to the device.